android_kernel_motorola_sm6375/arch
Repository files (latest commit first)
Filename Latest commit message Latest commit date
Helge Deller 945dc19778 parisc: Fix exception handler for fldw and fstw instructions
commit 7ae1f5508d9a33fd58ed3059bd2d569961e3b8bd upstream.

The exception handler is broken for unaligned memory acceses with fldw
and fstw instructions, because it trashes or uses randomly some other
floating point register than the one specified in the instruction word
on loads and stores.

The instruction "fldw 0(addr),%fr22L" (and the other fldw/fstw
instructions) encode the target register (%fr22) in the rightmost 5 bits
of the instruction word. The 7th rightmost bit of the instruction word
defines if the left or right half of %fr22 should be used.

While processing unaligned address accesses, the FR3() define is used to
extract the offset into the local floating-point register set.  But the
calculation in FR3() was buggy, so that for example instead of %fr22,
register %fr12 [((22 * 2) & 0x1f) = 12] was used.

This bug has been since forever in the parisc kernel and I wonder why it
wasn't detected earlier. Interestingly I noticed this bug just because
the libime debian package failed to build on *native* hardware, while it
successfully built in qemu.

This patch corrects the bitshift and masking calculation in FR3().

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-05 10:27:38 +02:00
..
alpha tty: the rest, stop using tty_schedule_flip() 2022-07-29 17:14:19 +02:00
arc
arm ARM: dts: qcom: pm8841: add required thermal-sensor-cells 2022-08-25 11:17:35 +02:00
arm64 crypto: arm64/gcm - Select AEAD for GHASH_ARM64_CE 2022-08-25 11:17:41 +02:00
c6x
csky
h8300
hexagon
ia64 ia64, processor: fix -Wincompatible-pointer-types in ia64_get_irr() 2022-08-25 11:17:25 +02:00
m68k
microblaze
mips MIPS: tlbex: Explicitly compare _PAGE_NO_EXEC against 0 2022-08-25 11:18:39 +02:00
nds32
nios2 nios2: add force_successful_syscall_return() 2022-08-25 11:18:28 +02:00
openrisc
parisc parisc: Fix exception handler for fldw and fstw instructions 2022-09-05 10:27:38 +02:00
powerpc powerpc/64: Init jump labels before parse_early_param() 2022-08-25 11:18:38 +02:00
riscv RISC-V: Add fast call path of crash_kexec() 2022-08-25 11:18:37 +02:00
s390 kexec, KEYS, s390: Make use of built-in and secondary keyring for signature verification 2022-08-25 11:18:11 +02:00
sh
sparc
um um: add "noreboot" command line option for PANIC_TIMEOUT=-1 setups 2022-08-25 11:18:34 +02:00
unicore32
x86 KVM: x86: Avoid theoretical NULL pointer dereference in kvm_irq_delivery_to_apic_fast() 2022-08-25 11:18:16 +02:00
xtensa
.gitignore
Kconfig